#include <stdio.h>
int main() {
    int a = 0;
    int b = 0;
    int c = 0;


    while (scanf("%d %d %d", &a, &b, &c) != EOF) {
        int arr1 = a + b;
        int arr2 = b + c;

        if (arr1 > c && arr2 > a) {
            if (a == b && b == c) {
                printf("Equilateral triangle!\n");
            }
            else if (a == b || b == c || a == c) {
                printf("Isosceles triangle!\n");
            }
            else {
                printf("Ordinary triangle!\n");
            }
        }



        else {
            printf("Not a triangle!\n");
        }

    }
    return 0;
}